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Gemmology Guides

The school's plain-language guides on identifying, grading and appraising gems, and the Singapore laboratories behind the certificates

These guides are written by the gemmology faculty of the Jewellery Design and Management International School. Each one takes a question buyers actually ask in Singapore and answers it with the same facts and instruments taught in the school's courses.

Identification

How to identify gemstones: the at-home tests that work, the ones that mislead, and when a laboratory is the only honest answer.
How to identify jade: jadeite versus nephrite, the Type A/B/C treatment grades, and why the letter decides the value.
Gem identification tools: what each instrument actually does, from refractometer to spectroscope.

Diamonds and grading

Lab-grown diamonds, explained: HPHT versus CVD growth, how laboratories tell grown from mined, and the questions to ask in a showroom.
Diamond grading in Singapore: what a grading report measures, which laboratories work here, and where to train.
Sapphires and rubies: judging corundum, the treatments that are normal and the ones that must be disclosed.

Appraisal

Jade appraisal in Singapore: what an appraisal establishes, who does it, and why treatment grade drives the number.

The laboratories behind the certificates

Every guide above ends up at a certificate. The companion Singapore gem labs guide profiles each laboratory in the city: NGI, FEGRI, Far East Gem Lab, Raffles GemLab and the rest, with what each actually does.

Go from reading to doing

The free tools make the guides interactive: the identification wizard walks a stone decision tree, the Name That Gem game tests you on real instruments, and the Gem Globe shows where each stone comes from. For structured learning, GT100 covers value factors and trade practice, and GT200 teaches the full instrument workflow with practice on up to 100 gems.

Learn this properly — gemmology at JDMIS, Singapore

Everything on this page is taught hands-on at JDMIS with real stones:

Gemmology: Secrets of the Gem & Jewellery Trade (GT100) — is where the trade knowledge behind these guides is taught in full
Gem Identification Methods (GT200) — hands-on instrument work: refractometer, specific gravity, microscope and UV, the way professionals actually identify stones.

Free tools while you read: Gem Globe (where stones come from) · Name That Gem (test your eye) · our guide to every Singapore gem laboratory.

Educational content by the gemmology faculty of the Jewellery Design & Management International School (JDMIS), Singapore. Gemmological constants quoted are standard reference values.